The Army Corps of Engineers turned down a key permit for a the Dakota Access pipeline.
Photograph: DDP USA/Rex/Shutterstock

The chairman of the Standing Rock Sioux tribe has asked the thousands of “water protectors” gathered in encampments along the Missouri river to “go home” after the US Army Corps of Engineers denied a permit for the Dakota Access pipeline to drill under the river.

In a video statement Dave Archambault thanked the thousands of Native American and environmental activists who travelled to North Dakota to help the tribe fight back against the pipeline, which they feared would contaminate their water source and destroy sacred sites.

But after the “huge victory” of the Army Corps decision, Archambault said: “There’s no need for the water protectors or for anyone to be putting ourselves in unsafe environments.

Archambault’s directive was rejected by many long-term water protectors, however, as the camps hunkered down amid a fierce blizzard.

“The chairman does not tell us what to do. The chairman is not in charge of the camp,” said Ladonna Bravebull Allard. “We stand. We don’t move. We don’t go nowhere.”

Allard, a member of the Standing Rock Sioux Tribe, founded the first of several “spiritual camps”, known as Sacred Stone, in April.

“We came to fight a black snake,” she said, referring to the pipeline. “Until it’s dead, we stand. That doesn’t mean put it five miles up the river. That means kill it dead.”

Many at the camps were suspicious that the permit denial was a “trick” intended to convince activists to leave so that the pipeline construction could continue unchallenged. Others feared that the Trump administration would reverse the Army Corps’ decision, or that the company would sue.

Though an administrative reversal would be subject to court review, according to the tribe’s lawyer, the pipeline company, Energy Transfer Partners, said in a statement on Monday that it intended to “complete construction of the pipeline without any additional rerouting”.

Archambault argued that it would not attempt to drill without the permit, known as an easement, because it would jeopardize the company’s investments.

Xhopakelxhit, who is Nuu Chah Nulth, Coast Salish, and Cree, said that opinions in the camp were divided about what to do next, with some wanting to stay and fight and others wanting to respect the wishes of the tribal leadership.

“He’s trusting bureaucracy and the government,” she said of Archambault. “When has the government ever treated Natives fairly?”

Xhopakelxhit also criticized the idea that rerouting the pipeline constituted a victory.

“If it’s not good for your people, Dave, then it shouldn’t be good for anyone,” she said.

Howaste Wakiya, an enrolled member of the coastal band of the Chumash Nation, rejected the idea that Archambault could direct the movement, which has garnered support from hundreds of indigenous tribes, as well as climate change activists, celebrities, and, this week, hundreds of US veterans.

“It was started in prayer, not in [the chairman’s] office,” he said.

However individual activists choose to proceed, few will be leaving immediately. The National Weather Service issued a blizzard warning on Monday for much of the state. Several inches of snow and wind gusts of up to 50mph were predicted through Tuesday evening.